Variability in climatology and agricultural production in China in association with the East Asian summer monsoon and El Nino Southern Oscillation

摘要

The East Asian monsoon (EAM) and the El Nino Southern Oscillation (ENSO) determine climate variability over much of East Asia, affecting vulnerable grain markets and food security in China. In this study, we investigated the variability of climate and of agricultural production in China in association with the East Asian summer monsoon (EASM) and ENSO. Data from China showed that a strong EASM decreased fall temperature in Gansu and Sichuan Provinces in western China, as well as winter temperature in Heilongjiang Province in NE China and in Shandong and Anhui Provinces in eastern China. Summer rainfall in Hunan Province in southern China increased in weak EASM years. Summer temperature increased in Heilongjiang in NE China and Gansu Province in NW China during the La Nina phase. Summer rainfall decreased in Gansu Province in NW China during the El Nino phase. Among staple crops in China (rice, wheat, maize), maize production was very vulnerable to a strong EASM and El Nino phase. In Henan Province in central China, seasonal climate variability associated with EASM and ENSO resulted in about 14.4 and 15.6 %, respectively, of maize yield variability. Maize Yield at the national scale decreased significantly by 5.2 % during the El Nino phase. Cropland area affected and damaged by floods in Hunan Province in southern China increased significantly by 11.3 and 8.5 %, respectively, in weak monsoon years. During the La Nina phase, total crop planting area increased significantly in Shandong, Henan and Anhui Provinces in central China, and in Heilongjiang Province in NE China; however, it decreased significantly in Sichuan Province in SW China. The large variability in seasonal climate and agricultural production in association with EASM and ENSO warrant applying EASM and ENSO information to agricultural and food market management.